Go Back  Offshoreonly.com > Technical > General Q & A
Merc 454 TPI work on 496 with no issues? >

Merc 454 TPI work on 496 with no issues?

Notices

Merc 454 TPI work on 496 with no issues?

Thread Tools
 
Old 10-31-2013 | 11:03 AM
  #1  
Thread Starter
Registered
10 Year Member
 
Joined: Oct 2013
Posts: 2,888
Likes: 148
From: SF Bay Area
Default Merc 454 TPI work on 496 with no issues?

I just picked up a 1997 Baja 272 Islander with a 496 crate motor installed with a carb instead of the 454 TPI that was pulled out due to a cracked block. I asked why he went with the carb and he is simply an old school hot rodder that hates messing with fuel injection.

I would much prefer the fuel injection and I did receive all of the parts along with the old motor in the sale, so are there any reasons/complications to prevent me from putting the FI back on?

Thanks in advance!

1997 Baja 272 Islander
Bravo1 drive with 23p Mirage plus prop.
Baja Rooster is offline  
Reply
Old 10-31-2013 | 11:24 AM
  #2  
Knot 4 Me's Avatar
Registered
20 Year Member
 
Joined: Jun 2005
Posts: 8,407
Likes: 797
From: Central IL
Default

What intake and carb was used on the 496? Does the old FI setup look like this?

https://www.mercruiserparts.com/Show...+INTAKE+PLENUM

Last edited by Knot 4 Me; 10-31-2013 at 11:26 AM.
Knot 4 Me is offline  
Reply
Old 10-31-2013 | 11:46 AM
  #3  
Registered
15 Year Member
 
Joined: Oct 2007
Posts: 8,439
Likes: 93
From: yorkville,il
Default

when you say crate motor,who bilt it.if it is a 8,1 L engine,the intake is completly different from a 454&502 engine.
mike tkach is offline  
Reply
Old 10-31-2013 | 11:59 AM
  #4  
Thread Starter
Registered
10 Year Member
 
Joined: Oct 2013
Posts: 2,888
Likes: 148
From: SF Bay Area
Default

Originally Posted by Knot 4 Me
What intake and carb was used on the 496? Does the old FI setup look like this?


https://www.mercruiserparts.com/Show...+INTAKE+PLENUM
Yes, that is the setup. It has an Edelbrock intake with an Edelbrock 700CFM carb. I'll have to check which version of manifold it is. It's not the Performer nor is it a tunnel ram, but somewhere in between. He did say that the carb was too small and an 800cfm would do the trick. The boat is in storage and the motor is in my garage, but it does look like everything should bolt up.

Originally Posted by mike tkach
when you say crate motor,who bilt it.if it is a 8,1 L engine,the intake is completly different from a 454&502 engine.
The 8.1 is completely different? I've built a few small block chevys, but the big blocks and marine engines are new animals to me.

It came off of ebay. Here's a link to what the motor most likely is. I'm still waiting for the paperwork from the previous owner.
http://www.ebay.com/itm/GM-8-1L-425h...47eb24&vxp=mtr

Last edited by Baja Rooster; 10-31-2013 at 12:04 PM.
Baja Rooster is offline  
Reply
Old 10-31-2013 | 12:28 PM
  #5  
Registered
15 Year Member
 
Joined: Oct 2007
Posts: 8,439
Likes: 93
From: yorkville,il
Default

the engine in the ebay ad is a 8.1 L 496,the 454&502 intake is not interchangable.you should not have a problem finding a fi unit from a 8,1L engine,i sugest calling raylor,they specialize in the 8,1L engine.
mike tkach is offline  
Reply
Old 10-31-2013 | 12:51 PM
  #6  
Thread Starter
Registered
10 Year Member
 
Joined: Oct 2013
Posts: 2,888
Likes: 148
From: SF Bay Area
Default

Got it, thanks. I'll just throw a bigger carb on there until I build up another motor then.

The previous owner bought the boat at an auction and found water in the oil and a freeze plug pushed out. Just for fun does anyone care to hazard a guess as to whether the crack is indeed cracked, or that it simply pushed water past a seal? It's a MarkVI 4bolt main block.
Baja Rooster is offline  
Reply
Old 10-31-2013 | 12:57 PM
  #7  
Registered
15 Year Member
 
Joined: Oct 2007
Posts: 8,439
Likes: 93
From: yorkville,il
Default

the block and or heads are probibally cracked,any good machine shop can magnaflux them for you.
mike tkach is offline  
Reply
Old 10-31-2013 | 01:06 PM
  #8  
Registered
15 Year Member
 
Joined: Oct 2007
Posts: 8,439
Likes: 93
From: yorkville,il
Default

on a side note,a 850 carb on the 8,1 should make your boat run good,if i were you id put the bigger carb on it and enjoy the boat.
mike tkach is offline  
Reply
Old 10-31-2013 | 01:23 PM
  #9  
Rookie's Avatar
Registered
20 Year Member
 
Joined: Jan 2003
Posts: 6,017
Likes: 1,519
From: Grand Rapids, MI
Default

I don't believe Edelbrock ever made an intake for an 8.1L 496. Only Dart made one to use a carb.
It must be a 454 stroked if it is a 496.

Correct me if I'm wrong.
Rookie is offline  
Reply
Old 10-31-2013 | 01:27 PM
  #10  
Registered
15 Year Member
 
Joined: Oct 2007
Posts: 8,439
Likes: 93
From: yorkville,il
Default

Originally Posted by Rookie
I don't believe Edelbrock ever made an intake for an 8.1L 496. Only Dart made one to use a carb.
It must be a 454 stroked if it is a 496.

Correct me if I'm wrong.
i was just on edelbrock,s site and could not find a manifold for thi 8,1 engine.maybe the op can post a pic of his engine
mike tkach is offline  
Reply


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.